If you've used ACR you'll be familiar with how this works, although this is a separate mod from ACR (and compatible with it). Forces the bed ownership system already in the game to actually work. Sims will autonomously only use the bed they have the most ownership of. Also includes a couple new pie menu options on the sim menu to set/clear bed ownership. In Hotels in Bon Voyage, bed ownership is currently not used. Sims can sleep in any bed as long as they are checked in. See the RTFM for the gory details. It may or may not conflict with another mod that affects sleep/relaxing.
Compatibility Notes: Pescado's bedsidefix from MATY conflicts with Smart Beds and is not necessary, that fix is included.